Sunni Islamic militants have stepped up efforts to expand their captured territory in northern Iraq, and their successes this week against what was thought to be a superior fighting force in the oil-rich, semi-autonomous Kurdish region have prompted President Obama to threaten airstrikes "if necessary" against the militants. The U.S. was also dropping humanitarian supplies by air to thousands of members of an Iraqi religious minority trapped in mountains and under siege by the Islamic extremists.

Gaza militants renewed rocket fire on Israel and Israel resumed airstrikes in Hamas-ruled Gaza after a three-day truce expired Friday and negotiations in Cairo on a new border deal for the coastal strip deadlocked.

"The fear is palpable," Monia Sayah says after returning from her latest assignment as a nurse with Doctors Without Borders. When Sayah arrived in Guinea in March, she couldn't have known she would witness the worst Ebola outbreak in history. Back then, there were 59 confirmed deaths from Ebola, a virus that can be fatal in up to 90 percent of cases. The death toll in West Africa has since soared.

What was the first of two hurricanes expected to hit the Hawaiian Islands has been downgraded. Iselle is now a tropical storm, with 70 mph maximum sustained winds. Iselle had been poised to be the first hurricane to hit the state in 22 years, and would be the first tropical storm to hit Hawaii in that time if, as expected, it makes landfall. A strong hurricane is following in Iselle's path. Hurricane Julio, a Category 3 storm, was about 1,000 miles behind in the Pacific. It's expected to pass just north of the islands sometime Sunday morning.

Prosecutors in Oscar Pistorius' murder trial insisted in closing arguments yesterday that the double-amputee former Olympian produced a succession of lies to cover up that he intentionally killed girlfriend Reeva Steenkamp after a fight. In a 109-page document detailing their entire case, prosecutors listed what they called 13 instances of "incongruities, deceit and tailoring" by Pistorius, who could be imprisoned for 25 years to life if convicted of premeditated murder. His lawyers were presenting their closing arguments today.

A group of high school cheerleaders from southeast Texas asked the state Supreme Court yesterday to rule on whether banners emblazoned with Bible verses that they display at football games are protected as free speech.

With a spike in shark sightings along busy West Coast beaches, Carter Evans reports scientists in California are creating a new tool in hopes of unlocking the many secrets of the great white shark -- an underwater drone that is programmed to act like a shark and follow the great whites.

New data from the Federal Reserve Board highlight how many Americans continue to struggle financially more than five years after the Great Recession. Nearly a quarter said they were "just getting by," while an additional 13 percent were struggling to make ends meet.